1. Home
  2. /
  3. CBSE
  4. /
  5. Class 11
  6. /
  7. The p-Block Elements class...

The p-Block Elements class 11 Notes Chemistry

myCBSEguide App

myCBSEguide App

Download the app to get CBSE Sample Papers 2023-24, NCERT Solutions (Revised), Most Important Questions, Previous Year Question Bank, Mock Tests, and Detailed Notes.

Install Now

CBSE Chemistry Chapter 11 The p-Block Elements in PDF are available for free download in myCBSEguide mobile app. The best app for CBSE students now provides The p-Block Elements class 11 Notes Chemistry latest chapter wise notes for quick preparation of CBSE exams and school based annual examinations. Class 11 Chemistry notes on Chapter 11 The p-Block Elements class 11 Notes Chemistry are also available for download in CBSE Guide website.

The p-Block Elements class 11 Notes Chemistry

Download CBSE class 11th revision notes for Chapter 11 The p-Block Elements class 11 Notes Chemistry in PDF format for free. Download revision notes for The p-Block Elements class 11 Notes Chemistry and score high in exams. These are the The p-Block Elements class 11 Notes Chemistry prepared by team of expert teachers. The revision notes help you revise the whole chapter in minutes. Revising notes in exam days is on of the best tips recommended by teachers during exam days.

Revision Notes for class 11 Chemistry Download as PDF

CBSE Class 11 Chemistry Quick Revision Notes Chapter 11 The p-Block Elements

  1. Group 13 Elements: The Boron Family
  2. Some Important Compounds of Boron
  3. Uses of Boron and Aluminium and their Compounds
  4. Group 14 Elements: The Carbon Family
  5. Some Important Compounds of Carbon and Silicon
  6. Uses of Compounds of Carbon and Silicon

Elements in which the last electron enters in to any one of the three p-orbitals of their outermost shells are called p-block elements.

p-Block of the periodic table is unique in terms of having all types of elements – metals, non-metals and metalloids. There are six groups of  p-block elements in the periodic table numbering from 13 to 18.

Their valence shell electronic configuration is ns2 np1–6(except for He). Differences in the  inner core of their electronic configuration greatly influence their physical and chemical properties. As a consequence of this, a lot of variation in properties among these elements is observed.

In addition to the group oxidation state, these elements show other oxidation states differing from the total number of valence electrons by unit of two.

While the group oxidation state is the most stable for the lighter elements of the group, lower oxidation states become progressively more stable for the heavier elements. The combined effect of size and availability of d orbitals considerably influences the ability of these elements to form π-bonds.

While the lighter elements form  bonds, the heavier ones form  or bonds. Absence of  d orbital in second period elements limits their maximum covalence to 4 while heavier ones can exceed this limit.

Group 13 Elements: The Boron Family

  • Members of this group are: boron (B), aluminum (Al), gallium (Ga), indium (In) & thallium (Tl).
  • Boron is a typical non-metal and the other members are metals.
  • There is availability of 3 valence electrons for covalent bond formation using four orbitals leads to the so called electron deficiency in boron compounds. This electron deficiency makes them good electron acceptor and thus boron compounds behave as Lewis acids.
  • Boron forms covalent molecular compounds with dihydrogen as boranes, the simplest of which is diborane,
  • Diborane contains two bridging hydrogen atoms between two boron atoms; these bridge bonds are considered to be three-centre two-electron bonds.

The important compounds of boron with dioxygen are boric acid and borax.

  • Boric acid, is a weak monobasic acid; it acts as a Lewis acid by accepting electrons from hydroxyl ion.
  • Borax is a white crystalline solid of formula . The borax bead test gives characteristic colours of transition metals.

Aluminium exhibits +3 oxidation state. Aluminium oxide is amphoteric. Aluminium halides, e.g., AlCl3 is dimer, acts as Lewis acid.

Atomic and ionic radii

  • The elements of this group have smaller size than the corresponding elements of second group.
  • On moving down the group, atomic and ionic radii increases due to the addition of new shells

Ionization energies

  • The first ionization energies of group 13 elements are less than the corresponding members of the alkaline earths.
  • The sharp decrease in ionization energies from B to Al is due to increase in size.

Electropositive or metallic character

  • The elements of group 13 are less electropositive as compared to elements belonging to group 2.
  • On moving down the group the electropositive (metallic) character increases because ionization energy decreases. For e.g., Boron is a non-metal, all other elements are typical metals.

Oxidation States:

With heavier elements,  +1 oxidation state gets progressively stabilised on going down the group. This is a consequence of the so called inert pair effect.

Group 14 Elements: The Carbon Family

Carbon is a typical non-metal forming covalent bonds employing all its four valence electrons  It shows the property of  catenation, the ability to form chains or rings, not only with C–C single bonds but also with multiple bonds (C=C or C≡C).

The tendency to catenation decreases as C>>Si>Ge  ~ Sn >Pb. Carbon provides one of the best examples of allotropy. Three important allotropes of carbon are diamond, graphite and  fullerenes.

  • Diamond: In diamond each carbon atom undergoes sp hybridisation. Each carbon atom is tetrahedrally linked to four other carbon atoms.
  • Graphite: carbon is sp2-hybridized. It has two dimensional sheet like structure having number of hexagonal rings fused together. Graphite conducts electricity along the sheet.
  • Fullerenes: is a form of carbon having a large spheroidal molecule made of a hollow cage of sixty or more atoms. Fullerenes are produced chiefly by the action of an arc discharge between carbon electrodes inside inert atmosphere.

The members of the carbon family mainly exhibit +4 and +2 oxidation states; compounds in +4 oxidation states are generally covalent in nature. The tendency to show +2 oxidation state increases among heavier elements. Lead in +2 state is stable whereas in +4 oxidation state it is a strong oxidising agent. Carbon also exhibits negative oxidation states.

It forms two important oxides: CO and . Carbon monoxide is neutral whereas is acidic in nature. Carbon monoxide having lone pair of electrons on C forms metal carbonyls. It is deadly poisonous due to higher stability of its haemoglobin complex as compared to that of oxyhaemoglobin complex. Carbon dioxide as such is not toxic. However, increased content of   in atmosphere due to combustion of fossil fuels and decomposition of limestone is feared to cause increase in ‘green house effect’. This, in turn, raises the temperature of the atmosphere and causes serious complications such as melting of glaciers.

Silica, silicates and silicones are important class of compounds and find applications in industry and technology.

Silicon dioxide has covalent three dimensional network. Each silicon atom is covalently bonded in a tetrahedral form to four oxygen atoms.

Silicones: Silicones are the synthetic organo-silicon polymers.

Silicates: are exist in nature in the form of zeolites, mica and asbestos, etc.

CBSE Class 11 Revision Notes and Key Points

CBSE quick revision note for class-11 Chemistry, Physics, Maths, Biology and other subject are very helpful to revise the whole syllabus during exam days. The revision notes covers all important formulas and concepts given in the chapter. Even if you wish to have an overview of a chapter, quick revision notes are here to do if for you. These notes will certainly save your time during stressful exam days.

To download The p-Block Elements class 11 Notes, sample paper for class 11 Chemistry, Physics, Biology, History, Political Science, Economics, Geography, Computer Science, Home Science, Accountancy, Business Studies and Home Science; do check myCBSEguide app or website. myCBSEguide provides sample papers with solution, test papers for chapter-wise practice, NCERT solutions, NCERT Exemplar solutions, quick revision notes for ready reference, CBSE guess papers and CBSE important question papers. Sample Paper all are made available through the best app for CBSE students and myCBSEguide website.

myCBSEguide App

Test Generator

Create question paper PDF and online tests with your own name & logo in minutes.

Create Now
myCBSEguide App

myCBSEguide

Question Bank, Mock Tests, Exam Papers, NCERT Solutions, Sample Papers, Notes

Install Now

Leave a Comment